Bracing of the lower limb is widely employed in orthopaedics, sports medicine and physiotherapy. Many well known methods and techniques are used.
The construction of the brace naturally tends to be related to the intended function. Thus, when it is required to simply provide a degree of support to the musculature of the thigh, seamless elastic fabric sleeves of the type made by surgical hosiers are often used.
However, in the technique of cast bracing for fractures, much more structural integrity is needed in the brace. This technique was pioneered by Professor Augusto Sarmiento in the nineteen-sixties and seventies. Hinges were developed to make an articulation between a lower or tibial cast member and an upper or femoral cast member. For many years, only Plaster of Paris was readily available for making cast members. These tended to be heavy and had a long period of setting-to-weight-bearing. Plaster of Paris is also radio-opaque which precludes monitoring of the fracture with the brace in situ.
So-called new casting materials of two main types were introduced in the late seventies and early eighties. Both resin-impregnated bandages and low-temperature thermoplastic sheets overcame the disadvantages of Plaster of Paris and its derivatives but these materials did not bond very effectively with the headplates used in the early hinge designs.
By the end of the seventies, several designs of hinge for the ankle in metal and in plastic had been introduced. These included types referred to as heel cups and sold by the United States Manufacturing Company of Pasadena, Calif. and Camp International of various addresses including Winchester, England.
At least one hinge for the hip was on sale in Europe--the Hynabrace Hinge made by Messrs Blatchford's of Basingstoke, England and sold by Messrs Smith and Nephew of Hull, England. This device was indicated for proximal third femoral fractures.
In response to a perceived need for cast bracing hinges which would mate well with new casting materials, one of the present inventors (D.E.Y.) and D. H. Boyes developed a new kind of hinge headplate. This is described in published U.K. patent application GR No. 2130488, published European application EPN No. 0 109 847, U.S. Pat. Nos. 4,467,792 and 4,559,935.
The present authors have gone on to develop a novel ankle hinge and a novel hip hinge disclosed in U.K. application No. 8501613 and in U.S. application Ser No. 734,050. More recently, they have disclosed a new type of hinge mechanism for knee hinges in U.K. application No. 8510,028 and in U.S. application Ser. No. 853,962, now abandoned.
Hinges designed for use in cast bracing have never been restricted solely to that application and it has been a frequent practice for orthotists and orthopaedic technicians to build them into orthoses, with or without casting material. An example we have encountered is the construction of hip orthoses used in Legg-Calve-Perthes disease where cast brace knee hinges have been modified and used.
Hinges of this general type have also been used in orthoses for supporting and bracing ligament injuries. A good example of this is a hinge according to Lerman, described in U.S. Pat. Nos. 4,337,764 and 4,372,298 and sold by Zinco Industries of Montrose Calif. This hinge is sold by itself for cast bracing and for surgical knee ligament repairs which are clear orthopaedic indications. However, this hinge is also built into a knee control orthosis which has indications ranging from minor knee instabilities to the protection of repaired ligaments in closely monitored rehabilitation programmes.
The latter type of indication derives mainly from sports medicine which has increased in importance in recent years as more and more people in western civilisations take part in widely varying sports.
There is little doubt that the increasing number of knee ligament injuries in particular, which are now being seen in general orthopaedic clinics, derive substantially from the fact that older and less fit people are jogging, skiing, playing soccer, rugby, American football and other games, often at a competitive level.
In the United States, bracing of joints, especially the knee, is well developed. The Lenox-Hill derotation brace, introduced in the sixties, was almost certainly the first to achieve widespread use. This device is well reviewed in an article by James A. Nicholas, M.D. entitled "Bracing the Anterior Cruciate Ligament Deficient Knee Using the Lenox Hill Derotation Brace" which appeared in Clinical Orthopaedics and Related Research Number 172, January-February 1983, Pages 137 to 142.
We have surveyed the field of sports medical bracing in the U.S.A. and Europe and have identified 18 different types which are important by virtue of widespread use or because they embody some feature specific to themselves. All were of U.S. manufacture, few bore any indication that any of their features were patented or the subject of pending applications. A number of other types and makes were found but they did not appear to contribute any extra features to the art.
Braces can generally be compared via a series of common elements such as hinge mechanisms, hinge arms, means of terminating hinge arms, wraps, securing means and accessories.